from machine import Pin
from utime import sleep, sleep_ms

Leds = [Pin(15, Pin.OUT), Pin(2, Pin.OUT), Pin(4, Pin.OUT), Pin(5, Pin.OUT), Pin(18, Pin.OUT), Pin(19, Pin.OUT), Pin(21, Pin.OUT), Pin(22, Pin.OUT)]

def dr():
    for i in Leds:
        i.value(1)
        sleep_ms(100)
        i.value(0)

def iz():
    for i in Leds[::-1]:
        i.value(1)
        sleep_ms(100)
        i.value(0)

while True:
    dr()
    iz()